Idon't understand. this question

Farnesene is a sesquiterpene. how many different isomers arising from double-bond isomerizations are possible? g

12. the amount of money in a bank account decreased by 21.5% over the last year. if the amount of money at the beginning of the year is represented by ‘n', write 3 equivalent expressions to represent the amount of money in the bank account after the decrease?

Ten times the square of a non-zero number is eqaul to ninety times the number